class_docstr: Pie graph class
code: def _compute_y_labels(self):
      pass
  
file_path: pygal/pygal/graph/pie.py
imports: from math import pi
  from pygal.adapters import none_to_zero, positive
  from pygal.graph.graph import Graph
  from pygal.util import alter, decorate
label_desc: Use image node_id 3 for calling the Pie obj's underlying member method code with example usage: obj._compute_y_labels() without return types